Fluid cooled grate



Dec. 4, 1 934. E. o. MARTY 7 1,982,918

I FLUID COOLED GRATE Filed Dec. 21, 1931 2 Sheets-Sheet l INVENTOR Edgar 0 Marty Dec. 4, 1934. Q MARTY 1,982,918

FLUID 000L313 GRATE Filed Dec. 21, 1931 2 Sheets-Sheet 2 INVENTOR l: JZdQaPOMaPZy Patented Dec. 4, 1934 UNITED STATES men-roam Application December 21, 1931,. Serial No. 582,310 6 Claims. (01. 110-74) This invention relates to grates and particularly to fluid-cooled grates.

An object of the invention is to continuously deliver air under pressure to a grate and utilize such air for cooling the grate as well as forsupporting fuel combustion thereon.

Another object is to continuously deliver air to a grate for supporting fuel combustion thereon, and to flow said air through a fluid passage in the grate in advance of its delivery to the burning fuel, whereby such air is preheated and the grate is cooled. Y

A furtherobiect is to arrange an air box beneath a grate which is apertured for the upflow of combustion-supporting air from said box and is further formed with a fluid passage, and to cool said grate and preheat the air delivered to said box by flowing such air through said fluid passage. I

Still another object is to provide for delivering a stream of air either directly to an air box underlying a grate or through fluid passages in the grate and thence to said air box.

A still further object-is to adapt any desired part of said air stream to be passed through said fluid passages of the grate.whileconcurrently admitting the remaining part of saidstream directly to said air box.

These and various other objects the invention attains by the construction hereinafter described, and illustrated in the accompanying drawings, wherein:

Fig. 1 is a view in side elevation of the improved grate, sectionally showing the front and rear walls of a furnace chamber, wherein said grate is installed, and showing in elevation a support for the grate positioned in front of said chamber, a provision for feeding fuel to the grate, and means for delivering air to the grate, under pressure.

Fig. 2 is a top plan view of the parts shown in Fig. 1, sectionally showing the walls of said furnace chamber, and omitting certain fuel feeding parts.

Fig. 3 is a longitudinal sectional elevation of the grate.

of tubular members 4, forming with said headers a rectangular frame, within which the tubes I extend. Surmounting said tubesand bridging the spaces therebetween is a plurality of elongated tuyere strips 5, preferably slightly arched from tube to tube.

To support said grate there is employed a pair of arms 6, formed preferably by steel channel beams having their rear end portions disposed beneath and rigidly secured to the ,mid portions of the members 4. Said beams extend forwardly from'the grate, convergently and at a downward inclination, being thus adapted to pass through the usual opening 7 giving accessto the ash-pit through the front wall 8 of the furnace.

The opening '7, is of less width than the grate, as is common practice, and it is preferred to provide the grate with a fuel feed extension 8a'of Sllfil-r ciently reduced width to project forwardly through said opening, above said beams;

In front of said wall and exterior to the furnace chamber, is positioned a support carrying the arms 6 and described grate. This support which-is more fully shown, described, and claimed in my copending applicationserial Number 582,- 309, filed, Dec. 2l, i931, comprises alaminated bar spring 9 having its ends secured inspaced trunnions l0, rotative in, a pair of standards 11 anchored to the furnace room; floor." Said trunnionsjointly carry a bracket 12 to which is secured a. blower 13, having its outlet 14 discharging into an air duct 15, rearwardly extending between the arms -6. Thus said duct inclines upwardly toward the grate and progressively increases in width correspondingly to the rearward divergence of said arms.

Underlying the grate and coextensive therewith in area, is an air box 16 formed preferably of sheet metal, into which the duct 15 discharges. Said air box is preferably carried by the arms 6, which may, in part, form the side walls of said box. A plurality of tuyre apertures 17, distributed with approximate uniformity throughout the length of each of the strips 5, provide for an upward discharge of combustion-supporting air from the box 16.

The front header 2 of the grate has an air delivery connection 18 thereto from the duct 15, said connection being equal in width and length to said header. The rear header 3 communicates throughout its width and length with the rear end of the air box. Thus air from the duct 15 may flow through the connection 18 into the front header of the grate and thence to the rear header through the several tubes 1 and side frame members 4, discharging from the rear header into the air box, as is indicated by the arrows in Fig. 3.

Located in the duct 15, just at the rear of the connection 18 is a damper 19 pivoted coincidently' with its horizontal median line, said damper being adjustable to deflect all or any desired portion of the air stream upwardly through the connection 18 to flow through the headers and tubes of the grate.

By thus flowing air through fluid passages of the described grate, preliminary to delivery of such air to the box 16, the grate may be safeguarded against such temperatures as might cause damage or deterioration, and there is'further accomplished a desirable heating of the air preliminary to its use for supporting combustion, whereby its efiiciency for such use is largely increased.

By properly adjusting the damper 19, the streamcf air delivered by the duct 15 may be so divided as to deflect a selected proportion of said stream through the fluid passages of the grate, thus affording accurate control of the cooling effect. 1

Unit assembly of the grate, its supporting frame and the underlying air box, and utilization of the arms 6 as a sole support for said assembly, and the mounting of said arms forwardly of and exterior to the furnace, are all features which expedite and facilitate installation of the grate, and which particularly adapt it for use in a furnace, already installed, by discarding the original grate of such furnace.

That is to say, the described grate requires no adaptation to the supports for a grate originally installed, which supports moreover would not lend themselves to the intended manner of grate operation. Moreover, if the furnace is particularly'designed to receive the described grate it is still decidedly advantageous to support the grate in the described manner because of the simplicity of installation and ready accessibility of the support and associated mechanism and safeguarding thereof from heat and ashes. I

While it is apparent that the illustrated embodiment of my invention herein disclosed is well calculated to adequately fulfill the objects and advantages primarily stated, it is to be understood that the invention is susceptible to variation, modification and change within the spirit and scope of the subjoined claims.

What I claim is:

1. The combination with a furnace wall, of a pair of spaced beams extending through said wall into the furnace, means coacting with said beams to form an air box between the beams and a duct betweenthebeamsleadingto said air box from the furnace exterior, a grate fullysupported upon said beams within the furnace and formed with a plurality of tuyere openings upwardly leading from said air box, and supporting means for said beams lying completely exterior to the furnace.

2. The combination set forth in claim 1, said beams converging from the grate to said furnace wall.

3. The combination set forth in claim 1, said beams and said duct extending from the grate in a downwardly divergent relation thereto.

4. The combination set forth in claim 1, said wall being the front wall of the furnace and being formed withan opening to accommodate said beams, said opening having a width less than the grate width, and said grate having a fuel feed extension of reduced width projecting through said wall.

5. The combination with a furnace comprising a grate, of a pair of arms extending through a Wall of the furnace and forming a sole support for said grate, an air duct carried by and between said arms, means for impelling air to said grate through said duct, and means for supporting said arms independently of and exteriorly to the furnace.

6. In a grate, a frame comprising a pair of tubular end headers and a pair of tubular side members terminally communicating with and rigidly connecting said end headers, a plurality of tubular grate bars connecting and communicating with the end headers, means for delivering air to one of said end headers, said grate bars and side members establishing a flow of such air to the other end header, and an air box beneath said grate having upward tuyere outlets between the grate bars, said side members rising above the grate bars to form fuel retaining side walls.

, EDGAR O. MARTY. 

